Functional textile structures

ABSTRACT

The invention provides a functional laminate composite fabric which is robust, laundry-durable and adaptable for securing about any three dimensional body, and a method for forming such fabric. The functional laminate fabric is provided with at least one functional element which can conduct electricity, conduct light, provide electromagnetic fields or provide shielding from electromagnetic fields. The functional laminate may include vias through which the functional element may be exposed. Generally, the functional laminate fabric is sufficiently robust for incorporation into garments and for applications in so-called wearable electronics.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. application Ser. No.11/570,310, filed Dec. 8, 2006, which was a national stage entry ofPCT/IB2005/001679, filed Jun. 15, 2005, which claimed priority from U.S.Provisional Application No. 60/581,048, filed Jun. 18, 2004.

FIELD OF THE INVENTION

The present invention relates to flexible textile structures, adaptedfor securing about a three dimensional object, having the ability toconduct electricity, conduct light, and provide or influenceelectromagnetic fields.

BACKGROUND OF THE INVENTION

Different types of flexible textile structures having an ability toconduct electricity or to influence electromagnetic fields have beendisclosed for certain medical and physiological monitoring applications.For example PCT publication WO 2003/087451A2 to Vikram Sharma (“Sharma”)discloses a tubular knit fabric system comprising an electricallyinsulating yarn, a stretch yarn, and a “functional” yarn knittedtogether to form a tubular knit fabric. In Sharma, the functional yarnis electrically conductive, having a resistance of 0.01 ohm/meter to5000 ohm/meter. The “functional” yarn is embedded within the tubularknit in a continuous spiral that extends the length of a sleeve formedfrom the tubular knit Body portions, such as limbs, are surrounded by aportion of the tubular fabric to measure physiological signs. Inaddition, these tubular knit fabrics disclosed by Sharma are adaptablefor use in a narrow elastic band configuration in which the functionalyarns serve as parallel conductors for electrical signals. Adisadvantage of Sharma's narrow elastic band structures is that thefunctional yarns or wires must be knitted simultaneously into thestructure with all other components.

In addition to electrically conducting elements, optical fibers forlight conduction have been disclosed for incorporation into garments.For example, U.S. Pat. No. 6,315,009 to Sundaresan Jayaraman et al.(assigned to Georgia Tech Research Corp.) (“Jayaraman”) discloses afull-fashioned continuously woven garment consisting of a comfortcomponent and sensing component of the base fabric. According toJayaraman, the sensing component can be an electrically conductivecomponent or a penetration sensing component. For example, thepenetration sensing component can be an optical conductor such asplastic optical fiber. A disadvantage of the Jayaraman construction isthe need to simultaneously weave directly into the tubular fabric orgarment the elastic yarn and the functional component(s), e.g. plasticoptical fiber.

The above references incorporate functional components, such aselectrical conductors, through the use of fabric structures of a wovenor knitted type. Such functional components can have poor compatibilitywith conventional textiles. Moreover, such functional componentsgenerally cause difficulties in conventional fabric forming processes(e.g. weaving, knitting, seamless knitting). For example, wires, smallcables, and plastic optical fibers often match poorly with typicaltextile fibers because of their fragility, elastic modulus,extensibility, and tensile strength. In particular, such disadvantagesare notable where elastic recovery and flexibility from the structure orgarment is desired and where the ability to wash or launder a garment isdesired. Thus, flexible textile structures are needed that can overcomeone or more deficiencies of the prior art.

The art continues to seek structures with elements able to conductelectricity, conduct light, or influence electromagnetic fields for usein certain medical and/or physiological monitoring applications, as wellas industrial and interconnect applications, wherein the structures donot have at least one of the deficiencies mentioned above. An ability toprovide a launderable garment that incorporates functional elements intoflexible textile-like structures without the need to knit or weave suchelements would be highly desirable.

SUMMARY OF THE INVENTION

The present invention relates to a functional laminate with asubstantially flat appearance. The functional laminate includes: firstand second outer layers of a fabric, paper or film; at least onefunctional element coextending with the first and second outer layers ofthe fabric or film; and an adhesive composition for bonding thefunctional element between the outer layers. The functional laminate ofthe invention can be conductive, and can, for example, conductelectricity, conduct light, or provide an electromagnetic field. In oneembodiment, a portion of the at least one functional element can beexposed through at least one hole or via provided in the laminate.

The present invention further relates to a method for preparing afunctional laminate with a substantially flat appearance. The methodincludes: providing a length of a first piece of inextensible materialhaving a first surface and a second surface; extending and fixing atleast one length of a functional element coextensively with theinextensible material, and securing the extended length of thefunctional element to the first surface of said first piece ofinextensible material along a substantial portion of the fixed lengththereof; providing a second piece of inextensible material having afirst surface and second surface, and securing said second piece ofinextensible material either to the functional element or to the firstsurface of said first piece of inextensible material along a substantialportion of the length thereof coextending with said functional elementto form the functional laminate. In one embodiment, the method furtherincludes forming a via in the functional laminate such that a portion ofthe functional element is exposed through said via.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described in the following detaileddescription with reference to the following drawings:

FIG. 1 is a schematic representation in side elevation of an apparatussuitable for making a functional laminate of the invention;

FIG. 2 is a schematic representation in top plan view of a portion of anapparatus for making a functional laminate of the invention;

FIGS. 3A and 3B are schematic representations in cross-section of afunctional laminate of the invention, illustrating a sandwich offunctional elements between two fabrics or sheets of other inextensiblematerial;

FIG. 4 is a schematic representation of an edge sectional view of afunctional laminate of the invention;

FIGS. 5A-5D are top plan views of perforation patterns that may be usedto form perforations in an outer sheet of the composite laminate toexpose functional elements;

FIGS. 5E and 5F are perspective views of functional laminates whereinportions of the functional elements are exposed through vias or holes inthe laminate; in FIG. 5E functional elements are exposed through anelongated slot-shaped perforation and in FIG. 5F four functionalelements are exposed through individual perforation holes;

FIG. 6A is a perspective view of a functional laminate of the inventionin which z-folds are formed at each end to stabilize the functionalelement within the laminate; and

FIG. 6B is a cross-sectional view in side elevation of a clampingengagement to provide one possible electrical connection means at thez-fold formed at one end of the functional laminate of FIG. 6A.

DETAILED DESCRIPTION OF THE INVENTION

The invention includes a functional laminate that may be a compositefabric with a substantially flat surface appearance. The laminate can beconductive, robust, laundry-durable, and adapted for securing about anythree dimensional body.

The functional laminate of the invention generally includes:

(a) first and second outer layers of nonwoven, knitted, or woven fabric,paper or film, wherein each layer has an inside (or first) surface andan outside (or second) surface with respect to the composite fabric;

(b) at least one functional element sandwiched between the outer layers;and

(c) an adhesive composition for bonding the first and second outerlayers, or for bonding the first and second outer layers to thefunctional element.

The two outer layers of nonwoven, knitted, or woven fabric, paper orfilm can, in one embodiment, be of substantially equal width.

In addition, the adhesive composition can, in one embodiment, comprisebetween about 8 and 70% of the laminate by weight, and although appliedto only partially cover the inside surface of at least one outer layer,such adhesive may penetrate to the outside of each outer layer to anextent less than about 10%, based on the surface area of each outerlayer.

Further, the functional element can be substantially parallel orcoextensive with at least one other functional element.

In addition, the functional laminate can be provided with at least onehole or via, which allows for the exposure of at least one functionalelement.

The invention further provides a method for making a functionallaminate, which includes the steps of:

providing a length of a first piece of inextensible material having afirst surface and a second surface;

extending and fixing at least one length of a functional elementcoextensively with the inextensible material, and

securing the extended length of the functional element to the firstsurface of said first piece of inextensible material along a substantialportion of the fixed length thereof;

providing a second piece of inextensible material having a first surfaceand second surface, and securing said second piece of inextensiblematerial either to the functional element or to the first surface ofsaid first piece of inextensible material along a substantial portion ofthe length thereof coextending with said functional element to form thefunctional laminate. Optionally, one or more perforations or holes areprovided in the functional laminate that serve as one or more vias toexpose the functional element. This method may further comprise the stepof attaching at least one connector to the functional laminate, whereinsaid connector is adaptable for connecting the at least one functionalelement in the laminate to a source selected from the group consistingof electricity and radiation. Radiation may be photonic radiationselected from those wavelengths of light employed in fiber opticnetworks for data communication.

In one embodiment of the inventive method, the outer layers aresubstantially planarized and secured in place when the at least onefunctional element is secured to such layers. As used herein, the term“planarizing” means to bring a portion of a fabric, a web, or a filminto a substantially planar and unwrinkled configuration withoutpuckers.

As used herein, suitable “substantially inextensible materials” includenonwoven fabrics, woven fabrics, knit fabrics, papers, oriented andunoriented films, including variants of the foregoing with metalliccoatings. These woven, nonwoven, and knit fabrics may comprise staple orcontinuous fibers, including those fibers from polyolefins, polyesters,polyamides, and polyperfluorinated olefins. Suitable films may comprisepolymers, including polyester, polyolefins, polyperfluorinated olefins,and polyamides. The fabrics or films of the outer layers of thefunctional laminate can include any of the above-mentioned substantiallyinextensible materials.

As used herein, the term “functional” means elements or materials thatexhibit electrical, optical, magnetic, mechanical, chemical, and/orthermal energy properties.

Examples of “functional materials” include, but are not limited to,materials that present: electrical function (e.g., electricalconductivity, heating, piezoelectric, electrostrictive, electrochromicactivity); optical function (e.g., photonic crystal fibers,photoluminesce, luminescence, light transmission, reflection); magneticfunction (e.g., magnetostrictive activity); thermoresponsive function(e.g., shape memory polymers or alloys); and sensorial function (e.g.,chemical, bio, capacitive). Such functional materials can be included infunctional elements used in embodiments of the present invention.

As used herein, suitable “functional elements” include: metallic wiresof the insulated or noninsulated variety, having one or more conductors,such as litz wire, tinsel wire, or stranded conductors for highfrequency use; single stranded metallic wires having circular ornoncircular cross-sections, such as, ribbon wire; metallic coatedpolymeric wires and films, such as, Xstatic® yarns and metallized MYLAR®(from DuPont-Teijin Films, Hopewell, Va., USA); inherently conductivepolymer fibers such as those from polypyrrole; plastic optical fiberfrom polymethyl methacrylate, such as, CROFON®; and silica glass opticalfibers of the multi-mode or single-mode variety suitable for fiber opticnetworks based on Ethernet, Fiber Channel, FDDI, ATM and Token Ringprotocols. Suitable functional elements also include the conductivestretchable composite yarns disclosed in PCT publication WO 2004/097089A1, the entire disclosure of which is incorporated herein by reference(hereinafter referred to as “electrically conductive composite yarnsthat comprise an elastic member surrounded by at least one conductivecovering filament”); as well as the elastomeric compositions disclosedin U.S. Provisional No. 60/562,622, filed Apr. 15, 2004, the entiredisclosure of which is incorporated herein by reference (hereinafterreferred to as “electrically conductive elastomeric compositions thatexhibit variable resistance”).

As used herein, the term “adapted for securing about any threedimensional body” means the functional laminate is flexible allowingconformance to any shape. Particularly, where the functional laminate isa garment or a component of a garment or other wearable placed on atleast a portion of a body, the laminate is at least as adaptable as thegarment or wearable in conforming to the three dimensional shape of thebody. Inherent in the adaptable conformance of the laminate to any threedimensional body is a robustness of the laminate structure to maintainthe performance of the laminate's functional element in the presence ofany motion of the three dimensional shape to which the laminate isconforming.

As used herein, the term “laundry durable” means the functional laminateis at least washable. Particularly, where the functional laminate is acomponent of a washable garment or other washable wearable placed on thebody, the laminate structure maintains the performance of the laminate'sfunctional element after multiple washing or laundry cycles. Forexample, maintaining functional element performance after at least onewash cycle would be “laundry durable.”

As used herein, the term “conductive” means at least a portion of thelaminate conducts electricity, conducts light, or is able in provide anelectromagnetic field, or is able to provide shielding fromelectromagnetic fields.

As used herein, the term “substantially parallel or coextensive” meansthat the functional element(s) extend lengthwise in the same directionof the functional laminate (also known as the “machine direction”)without contacting an adjacent functional element. Such substantiallyparallel or coextensive elements can be, in at least one embodiment,substantially equidistant from the other functional elements(s) alongtheir length in the direction perpendicular to the direction in whichthey extend. For example, when a functional element extends in themachine direction of the functional laminate, then another substantiallyparallel or coextensive functional element also extends in the machinedirection, and both elements are substantially equidistant from eachother in the direction perpendicular to the machine direction at pointsalong their length. Nonwoven fabrics suitable for making functionallaminates of the invention can have a basis weight ranging from about 10to about 100 grams/(meter)², such as from about 10 to about 30grams/(meter)². Many types of nonwoven fabrics are suitable for use inembodiments of this invention. Representative examples include nonwovenscomposed of thermally bonded, spunbonded, and hydroentangled fibers. Forexample, they may be composed of synthetic polymeric fibers such aspolyolefin, polyester, and polyamide fibers.

The functional laminate of the invention comprises a middle “layer” ofat least one functional element sandwiched between the outer layers ofinextensible material, such as nonwoven fabrics or films.

The functional element(s) in this middle “layer” may, in one embodiment,be a metallic wire of the insulated or uninsulated variety. For example,single conductor wire may be used. The use of more conductors per wire,such as litz wire or stranded conductors, is suitable for high frequencyelectrical use. A single stranded metallic wire having a circular ornoncircular cross-section, such as ribbon wire, is suitable for highcurrents or where a more rigid laminate is preferred. In addition, flatmetallic wires, may be used such as the flat copper wire (insulated ornon-insulated) from REA Magnet Wire Co., Fort Wayne, Ind. Certainmetallic coated polymeric fibers may also be used, such as, Xstatic®yarns, which are silver plated textile nylon filaments available fromLaird Sauquoit Technologies, Inc. (300 Palm Street, Scranton, Pa.,18505) under the trademark X-static yarn. One suitable form of X-Static®yarn is based upon a 70 denier (77 dtex), 34 filament textured nylonavailable from INVISTA S. à r. l., Wilmington, Del. as product ID70-XS-34×2 TEX 5Z electroplated with electrically conductive silver.Another suitable conductive yarn is a metal coated KEVLAR® yarn known asARACON® from E. I. DuPont de Nemours, Inc., Wilmington, Del. Also usefulin embodiments of the invention are members of the class of inherentlyconductive polymer fibers, such as those from polypyrrole. In addition,the plastic optical fiber (POF) from polymethyl methacrylate polymersmay be used. Where a functional element for guiding light is desired, aPOF, such as CROFON® may be used. Useful POF may, for example, be of thestep-index type (SI-POF) or the graded index type (GRIN-POF) for higherspeed optical communications. The class of silica glass optical fibersof either the multi-mode or single-mode variety also comprise a usefulclass of functional elements suitable for fiber optic networks based onEthernet, Fiber Channel, FDDI, ATM, and Token Ring protocols.

In addition, the functional element can comprise a conductive yarn, suchas of Xstatic® yarn or fiber twisted together with wire, for example,copper wire. The functional element can further comprise electrically oroptically functional composite yarns that comprise an elastic membersurrounded by at least one functional covering filament or electricallyconductive elastomeric compositions that exhibit variable resistancetwisted together with Spandex and/or Xstatic® yarn.

The layers of the functional laminate are bonded together by an adhesivecomposition. Each element in the composite should be bonded to at leastone other element of the composite. For example, an adhesive may beapplied to the functional element, and in turn that element may beadhered to inner surfaces of the outer layers. As another example, anadhesive may be applied to an inner surface of one of the outer layers.The adhesive composition can, for example, constitute from about 8% to70% of the weight of the composite fabric. Adhesive content in thefunctional laminate above these levels may, in certain circumstances, bedisadvantageous, as the fabric may bond to itself. Suitable adhesivecompositions can, for example, be hot melt adhesives, such asstyrene-based block copolymers, including styrene/isoprene andstyrene/butadiene block copolymers. Bonding by other methods may bepossible, such as flame lamination and laser or ultrasonic welding, ifsuch techniques can be carried out without harming the functionalelement.

The number of functional elements per inch of width of laminate materialis not limited and can, for example, range from 1 to 20, such as from 5to 10.

The apparatus schematically represented in side elevation in FIG. 1 maybe used in the process of making functional laminates falling within thescope of the present invention. FIG. 1 shows supply rolls 2 and 4 offunctional elements 5 and 10 (copper wire, for example). However, aplurality of supply rolls and functional elements is also contemplated(see, for example, FIG. 2, which shows supply rolls 2, 2′, 4, 4′, and 4″of functional element 5, 5′, 10, 10′, and 10″). A functional elementcan, for example, be uniformly tensioned between roll 15 and nip rolls50 (or roll 15′ and nip rolls 50) to provide stability, but generallysuch functional elements 5 and 10 are not substantially elongated. InFIG. 1, the functional elements 5 and 10 are shown as being side-by-sideand may be separated on any pitch over the roll surface of guide plate25. Where multiple functional elements are supplied to the process (seeFIG. 2 where the machine direction, M, of the process is indicated), itis understood that the guide plate 25 (in FIGS. 1 and 2) or anequivalent spacing means can provide the position and pitch of eachfunctional element. In FIG. 1, a layer of substantially parallelfunctional elements 5 and 10, are shown as being placed on top of one ofthe layers of nonwoven fabric 35 supplied from rolls 33. An adhesive 30,for example, a hot melt adhesive, is applied onto the functionalelements and bottom nonwoven layer via conduit 20. The other layer ofnonwoven 35′, supplied from rolls 33′, is then placed on top of theadhesive-treated combination at roll 40 and the combined structure isbonded by heat and pressure at nip rolls 50. Alternatively, the adhesive30 can be applied to the functional elements prior to their placementbetween layers of nonwoven fabric. When the bonding is completed, theuniform tension is substantially completely released and the compositefabric relaxes to form the desired structure 55. Arrow D indicatesdirection of travel of the produced structures 55 away from the niprolls 50.

The hot melt adhesive 30 (see, for example, FIG. 2) can be applied inseveral different ways. In one method, the melted adhesive can bedeposited as a discontinuous web from a spray nozzle (one such nozzle 22is shown at the end of adhesive conduit 20 in FIG. 2), by a processknown as melt blowing. In another method, the melted adhesive can bedeposited as a solid stream from a nozzle that moves in a spiral patternas the web passes, by a process known as spiral spray. A pattern inwhich the adhesive only partially covers the non-woven layers, such asis produced by melt-blowing or spiral spray, can result in a uniform,flat surface appearance of the composite fabric. By “only partiallycovers” it is meant that the adhesive is present at one part of thenonwoven but absent at an adjacent part. This can also be accomplishedby applying a “dot matrix” pattern.

FIG. 3A and FIG. 3B illustrate functional laminate structures withdifferent functional elements 5 and 5 b. In FIG. 3A, functional element5 is a copper wire. In FIG. 3B, functional element 5 b is ribbon wire.In FIGS. 3A and 3B, nonwoven fabrics 35 and 35′ are as described forFIGS. 1 and 2.

The functional laminate may be “laundry durable” meaning that it canundergo at least one laundry cycle without showing evidence ofdelamination of the outer layers (whether polypropylene or polyesterfiber-based nonwovens), which would indicate loss of bonding between thefunctional element(s) and the outer layers. The functional laminate mayalso be disposable, for example, when at least one of the outer layerscomprises paper.

The functional laminate fabric may, in certain embodiments, be furthercharacterized by laundry durability such that it can undergo at leastabout 28 laundry cycles without showing evidence of delamination of theouter layers. To demonstrate such durability, the following laundrycycle is used: 30-minute warm wash/warm rinse with 38-41° C. (100-105°F.) water and 50 g of “Tide” detergent in a Sears Kenmore Series 80washer, followed by drying on the “normal/permanent press/medium”setting (up to 96° C. (205° F.)) in a Sears Kenmore Series 80 dryer.

The laundry durability of these functional laminate fabrics can beprovided by using selected adhesives having a complex viscosity at 120°C. of: (i) at least about 25 pascal seconds (250 poise) when the outerlayers comprise nonwoven fabric that comprises polypropylene fibers; and(ii) at least about 200 pascal seconds (2,000 poise) when the outerlayers comprise nonwoven fabric that comprises polyester fibers.

The absolute value of the complex viscosity is defined as follows: At agiven frequency, ω, and shear stress, σ, the absolute value of thecomplex viscosity, |η*|, is the square root of the sum of the squares ofthe elastic, (G′), and viscous, (G″), moduli divided by the frequency:

|η*|=√G′ ² +G″ ²/ω

The softening point of useful adhesives can generally be expected toexceed 90° C. (194° F.) and suitably can generally be expected to exceed110° C. (230° F.).

Examples of adhesives useful in making laundry durable functionallaminate fabrics include those that contain styrene-based blockcopolymers, which may also contain additives, such as tackifying agentsand processing oils. Where the nonwoven fabrics comprise polypropylenefibers, the adhesives can include HL-1486 and HL-1470 (H. B. FullerCompany), and H-2104, H-2494, and H-2385 (Bostick, Inc., Milwaukee,Wis.). Where the nonwoven fabrics comprise polyester and/orpolypropylene fibers, the adhesives can include H-2385 (Bostick, Inc.,Milwaukee, Wis.) and NS-34-3260, NS-34-3322, and NS-34-5640 (NationalStarch Company). All of the above-named adhesives contain styrene-basedblock copolymers. The complex viscosity of selected adhesives that areuseful in making the laundry-durable functional laminate fabrics of theinvention are disclosed in EP1 128 952 B1 (granted 20031126 and assignedto E. I. DuPont de Nemours and Co.), the entire disclosure of which isincorporated herein by reference.

FIGS. 5A through 5D are top plan views of perforation patterns that maybe used in conjunction with the invention. In FIG. 5A, a series ofeleven round hole perforations 70 a are formed in a regular gridpattern. In FIG. 5B, a series of fourteen round hole perforations 70 bare formed an alternate regular grid pattern. In FIG. 5C, a rectangularslot perforation 72 is shown, oriented with its longest side generallyperpendicular to the lengthwise-extension of the sheet holding suchpattern and thus generally perpendicular to the extended length of thefunctional element. In FIG. 5D, a trapezoidal slot perforation 74 isshown, oriented at a slant with respect to the lengthwise extension ofthe sheet holding such pattern. The pattern sheets in FIGS. 5A to 5D arerepresentative of the types of patterns that may be employed. Otheradvantageous patterns may be designed to meet specific requirements.Preferably, the patterns are cut through one outer layer of thefunctional laminate, either while the layer is held in a planarized andfixed position or prior to assembling such layer within the functionallaminate. Optionally, such patterns may be cut through both outer layersof the functional laminate.

FIGS. 5E and 5F are perspective views of functional laminates whereinportions of the functional elements are exposed through vias or holes inone outer layer of the laminate. In FIG. 5E, functional elements, 76 aand 76 b, are exposed through an elongated slot-shaped perforation 74.In FIG. 5F, four functional elements, 78 a, 78 b, 78 c, and 78 d, areshown each exposed through an individual perforation hole.

FIG. 6A is a perspective view of a functional laminate 55 of theinvention comprised of two nonwoven fabrics, 35 and 35′, and having twofunctional elements, 5 and 5′, and including a folded over portion 100or z-fold at each end. The folded over portion 100 functions as a strainrelief, to help maintain the functional elements within the laminatestructure.

The folded over portion 100 also permits a connector means to be clampedabout the folded over portion. In FIG. 6B, an end portion of a laminateis represented in cross-section includes a clamping means comprising afirst portion 110 and a second portion 120. The first portion 110 of theclamping means is provided with at least a pair of threaded holes eachadapted to receive the threads of a bolt 130, which passes through thesecond portion of the clamping means 120 and engages the threads ofportion 110. In FIG. 6B, the two portions of the clamping means 120 and110′ represented in cross-section, are completely engaged by means ofthe threaded bolts and provide a tight clamping of the folded overportion of laminate 55.

The invention is further illustrated in view of the Examples below.

EXAMPLES

The samples in these examples were made using a nonwoven fabric fromTable 1 and a functional or conductive element from Table 2.

TABLE 1 Nonwoven Fabric Used Id Description Supplier NW1 Ahlstrom 50 gsmwet laid Invista Polypropylene NW2 Avgol 15 gsm spunbonded Perkin Sales,Inc., Edisto Island, SC Polypropylene 29438, USA NW3 Ahlstrom 62 gsm wetlaid Invista polypropylene NW4 SMS PP 30 gsm Bostik Inc., Milwaukee, WI,USA NW5 SMS PP 15 gsm Bostik Inc., Milwaukee, WI, USA NW6 Avgol 50 gsmspunbonded Perkin Sales, Inc., Edisto Island, SC Polypropylene 29438,USA

TABLE 2 Functional or Conductive Element Used ID DescriptionManufacturer Cu1 Copper flat wire 0.05″ × 0.003″ Rea Magnet Wire, Inc.,tin plated Fort Wayne, Indiana, USA Cu2 Copper flat wire 0.058″ × 0.003″Rea Magnet Wire, Inc., insulated with polyester Fort Wayne, Indiana, USACu3 Copper flat wire 0.05″ × 0.003″ Rea Magnet Wire, Inc., withpolyester insulation Fort Wayne, Indiana, USA XCu1 Twisted Xstatic ®8ply 70f34 Tex Produced in-house with Non-HS with two 36awg Silvercommercially available coated Cu wires yarns/wires Xs1 Xstatic ® silvercoated nylon 8ply Sauquiot Industries Inc., 70f34 Tex non-HS Scranton,PA USA Xs2 Xstatic ® silver coated nylon 8ply Sauquiot Industries Inc.,70f34 Flat HS (2 hr 190 F.) Scranton, PA USA

Each of the test samples was washed as described below and theelectrical resistance or conductivity was measured in the manner knownto those skilled in the art of electrical measurement. The washdurability testing method was comprised of a machine wash cycle withwarm (40° C.) water and a cold rinse (room temperature water) usingAmerican Association of Textile Chemists and Colorists (AATCC) WOBStandard Powder Detergent with a hanging to dryness phase at roomtemperature.

Example 1

In the examples shown in Table 3, a 2 to 5 inch (5.1 to 12.7 cm) widefunctional laminate was prepared using the apparatus schematicallyrepresented in FIG. 1. The laminate had functional elements as shown inTable 3 and described in Table 2. The functional elements were suppliedfrom rolls under tension to the apparatus illustrated in FIG. 1. A pitchof 0.1 inch to 0.2 inch (2.5 to 5.8 mm) was used, as shown in Table 3,for different examples. The two layers of nonwoven fabric were suppliedby rolls to the apparatus shown in FIG. 1 (see, for example, the rolls33 and 33′) under sufficient tension to effectively planarize the twononwoven fabrics. Typically, the conductive element was introduced intothe structure before the adhesive was introduced. However, as indicatedin Table 3, the adhesive was also introduced, in some samples, beforethe conductive element.

For all samples, the adhesive was melt blown just before contacting thebottom layer of nonwoven fabric. For all samples, a styrene/isopreneblock copolymer-based adhesive was used (product of Bostik Inc.,Wawatosa, Wis., USA), at different rates, as shown in Table 3. Theadhesive was applied at 149° C. The speed of the samples entering a pairof nip rollers (substantially the same as schematically represented bynip rolls 50 in FIG. 1) varied from 50 ft/min to 200 ft/min (15.2 to61.0 m/min), as shown in Table 3, using an adequate nip roll pressure.The top and bottom layers of nonwoven fabric and conductive filamentsbecame adhesively bonded by this process.

Table 3 shows the electrical resistance data (in Ohms/meter) for 50 cmlength samples after being subjected to the number of wash cyclesindicated. As can be seen from the Table, wash testing of the samplesshowed no profound change in DC electrical resistance for eachindividual conductive element, other than a small increase to less twotimes the before washing resistance.

TABLE 3 Electrical Resistance (Ohms/meter) Non- Adhesive woven Type &Wire 0 5 10 15 20 25 Sample ID Id &gsm mg/sqin Id Pitch washes washeswashes washes washes washes 0504084 NW3 - 62 gsm H-2766 Cu1 0.20 in. 0.20.2 0.4 Broke NW3 - 62 gsm 10 mg/in² Cu1 0.3 0.2 Broke Broke Cu1 0.2 0.5Broke Broke 050427-1 NW1 - 50 gsm H-2766 Cu1 0.10 in. 0.3 0.4 BrokeBroke NW1 - 50 gsm Cu1 0.4 0.5 Broke Broke Xs1 56 60 58 62 Xs1 58 68 6063 050427-2 NW1 - 50 gsm H-2766 Cu1 0.10 in. 0.4 0.4 Broke Broke NW2 -15 gsm 12 mg/in² glue Cu1 0.4 0.5 Broke Broke Xs1 56 68.6 54 60 Xs1 5765.4 64 70 Xs1 52 58.6 66 71 Xs1 56 65.4 64 68 050427-3 NW3 - 62 gsmH-2766 Cu1 0.10 in. 0.4 0.4 Broke Broke 22 mg/in² glue Xs1 53 60 64 68Xs1 55 66 66 69 Xs1 54 66 64 67 050503-1 NW2 - 15 gsm H-2766 XCu1  0.1in 0.8 0.9 1.1 10.3 25.4 NW2 - 15 gsm XCu1 0.8 0.9 1.1 15.4 28.3 Xs1 5058 62 65 78 Xs1 54 59 65 70 80 050503-2 NW1 - 50 gsm H-2766 Cu2 0.10 in.0.2 0.3 0.2 0.3 0.3 NW1 - 50gsm Cu2 0.3 0.4 0.3 0.4 0.2 Xs1 52 59 65 7378 Xs1 53 61 68 75 79 050518-1 NW4 - 30 gsm H-2385 Cu3 0.10 in 0.2 0.30.2 0.2 0.2 NW4 - 30 gsm 10 mg/in² Cu3 0.2 0.2 0.2 0.2 .03 50fpm Xs2 5154.8 68 84.6 98.7 Xs2 53.2 64.6 65 86.4 97.6 Xs2 54 61 66.2 84 95.6 Xs251 58.2 65.4 84.6 94.8 050518-2 NW4 - 30 gsm H-2385 Cu3 0.10 in. 0.3 0.20.2 0.2 NW4 - 30 gsm 20 mg/in² Cu3 0.2 0.3 0.3 0.2 0.2 50fpm Xs2 55 68.470 84.2 0.3 100fpm Xs2 53.2 64 72 78 96.5 200fpm Xs2 53 58 64.8 83.496.4 Xs2 53.4 59.2 68 82.4 95.4 050519-3 NW5 - 15 gsm H-2385 Cu3 0.10in. 0.2 0.2 0.2 NW5 - 20 mg/in² Cu3 0.2 0.2 0.3 15 gsm 50fpm adhesiveapplied Xs2 54.6 68 74.6 after the yarn Xs2 53.2 66.8 74.6 contact Xs253.8 67.4 78.2 Xs2 54.2 66.5 78.4 050519-4 NW5 - 15 gsm H-2385 Cu3 0.10in. 0.2 0.2 0.3 NW5 - 15 gsm 20 mg/in2 Cu3 0.2 0.2 0.3 50fpm adhesiveapplied Xs2 54.6 67.8 72.4 before the yarn Xs2 55.4 69.3 76.6 contactXs2 52.6 68.4 76.4 Xs2 54.2 65.8 78.2 050519-5 NW6 - 50 gsm 20 mg/in2Cu3 0.10 in. 0.2 0.2 0.2 NW6 - 50 gsm applied after Cu3 0.0 0.3 0.250fpm functional Xs2 52.4 68.5 76.4 elements Xs2 54.6 65.4 76.8 Xs2 57.064.3 78.2 Xs2 55.2 65.9 74.8

Example 2

This example provides a laminate that has at least one modified outerlayer. As in previous examples, copper-based conductive elements, wires,ribbons, and/or metallic plated yarns can be introduced between twonon-woven layers. The conductive element(s) are bonded between twolayers of the nonwoven fabric with a hot melt adhesive. The two layersof nonwoven fabric are, as in Example 1, supplied on rolls (such as 33and 33′ in FIG. 1) under sufficient tension to effectively planarize thetwo nonwoven fabrics. The conductive elements (copper ribbons) are in arelaxed state under no tension and the adhesive is melt blown onto thebottom layer of nonwoven fabric.

In this example, perforations are provided in one of the outer layers atintervals along a path substantially co-linear with the one of theconductive elements, e.g. co-linear with at least one of the two copperribbons. These perforations in the outer (nonwoven) layer are punctuatedalong the length of the nonwoven material. Such perforations are alsoknown in the electrical and electronic arts as “vias” (vias areconstrued here to mean a through-passage communicating from one surfaceto another and through which a wire or functional element passes, sothat the wire is underneath the via).

As shown in FIG. 5, the perforations can, for example, be geometricshaped rectangles or circular cross-sectionally shaped holes obtained bya “hole-punching” means. Any cross-sectional shape is generally suitableand is readily provided by a hole punch die having the desired shape.Hole-punching means can, for example, include a hand held device, whichproduces a single hole, and a 3-hole paper punch used to make 3-ringbinder holes in paper. In general, such hole-punching means are used ina step-and-repeat fashion to make a series of holes of a fixed spacinginterval in the non-woven.

Alternatively, the non-woven sheet may be fed through a dedicated holepunching apparatus capable of hole punching on a fixed spacing intervalor on a randomly spaced interval selected by the operator. Alternately,the non-woven sheet may be scored. The non-woven sheet, so perforated,can be wound up in a conventional manner to then be mounted in anapparatus (such as that shown in FIG. 1, in either or both of positionsdenoted as 33 or 33′). In an alternative embodiment, vias can be cut inany shape directly into multiple layer depths of an un-wound roll. Theperforated non-woven can then used to form a functional laminate.

Nothing in this specification should be considered as limiting the scopeof the present invention. All examples presented are representative andnon-limiting. The above described embodiments of the invention may bemodified or varied, and elements added or omitted, without departingfrom the invention, as appreciated by persons skilled in the art inlight of the above teachings. It is therefore to be understood that theinvention is to be measured by the scope of the claims, and may bepracticed in alternative manners to those which have been specificallydescribed in the specification.

1. A method for preparing a functional laminate with a substantiallyflat appearance, comprising: providing a length of a first piece ofinextensible material having a first surface and a second surface,wherein said first piece of inextensible material is provided with oneor more predetermined vias therethrough; extending and fixing at leastone length of a functional element coextensively with the inextensiblematerial, and securing the extended length of the functional element tothe first surface of said first piece of inextensible material along asubstantial portion of the fixed length thereof; providing a secondpiece of inextensible material having a first surface and secondsurface, and securing said second piece of inextensible material eitherto the functional element or to the first surface of said first piece ofinextensible material along a substantial portion of the length thereofcoextending with said functional element to form the functionallaminate, wherein the functional element does not penetrate into orthrough either of the first piece of inextensible material or the secondpiece of inextensible material and at least a portion of the functionalelement is exposed to an environment external to the functional laminatethrough the at least one via.
 2. The method of claim 1, wherein at leasttwo lengths of functional elements are extended and fixed to besubstantially parallel or coextensive.
 3. The method of claim 1, whereinthe functional element is selected from the group consisting of:insulated single and multi-stranded metallic wires, noninsulated singleand multi-stranded metallic wires, metallic coated polymeric fibers,inherently conductive polymer fibers, plastic optical fiber, silicaglass optical fibers, and metallic coated films.
 4. The method of claim1, wherein the inextensible material is a fabric or film selected fromthe group consisting of nonwoven fabric, woven fabric, knit fabric,paper, and polymer film.
 5. The method of claim 1, further comprisingperforating the first piece of inextensible material to form the atleast one via opening.
 6. The method of claim 5, wherein the at leastone via opening is selected from the group consisting of a hole, a slitor a slot.
 7. The method of claim 6, further comprising perforating thesecond piece of inextensible material to form at least one other viaopening.
 8. The method of claim 1, further comprising the steps of: (i)folding a distal end of the functional laminate back onto itself atleast one time; and (ii) fastening such folded end to an outer surfaceof one outer layer.
 9. The method of claim 8, wherein fastening is by amechanical fastening mechanism selected from the group consisting ofgluing, riveting, snapping, stitching, stapling, welding, and encasing.10. The method of claim 1, further comprising the step of attaching atleast one connector to the functional laminate, wherein said connectoris adaptable for connecting the at least one functional element in thelaminate to a source selected from the group consisting of electricityand radiation.
 11. The method of claim 10, further comprising connectinga source of electricity to the at least one functional element.
 12. Themethod of claim 10, further comprising connecting a source of radiationto the at least one functional element.